Living with obesity: My genes mean I m hard-wired to store fat bbc.co.uk - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from bbc.co.uk Daily Mail and Mail on Sunday newspapers.
Dr CHRIS VAN TULLEKEN: A mere four weeks - that s all it took for me to pile on enough fat to move from being a healthy weight to being overweight, putting my health at real risk.